4'-Demethyl-epipodophyllotoxin-alkylidene-.beta.-D-glucoside (hereinafter referred to as "etoposide") has heretofore been well known as a compound having an antitumor effect by U.S. Pat. No. 3,524,844 and the like.
In order to develop a more excellent antitumor agent, the present inventors have made an extensive study and have consequently found that a compound of the general formula (I) has an excellent antitumor activity and has a very high water solubility as compared with etoposide, whereby this invention has been accomplished.